1. Field of the Invention
This invention relates to oral inflation tubes for inflating inflatable articles such as personal flotation devices, rafts, buoys and emergency signalling equipment. Additionally, this invention relates to relief valves used in connection with such inflatable articles.
1. Description of the Background Art
Presently, there exists many types of inflatable articles such as personal flotation devices (life vests, rings and horseshoes), life rafts, and emergency signalling equipment. Typically, such inflatable articles include an inflator, to which is connected a compressed gas cartridge, for inflating the article either manually or automatically, a relief valve to vent air from the article in the event of over inflation, and an oral inflation tube to permit oral inflation. U.S. Pat. No. 3,809,288 discloses a manual inflator and U.S. Pat. Nos. 3,997,079, 4,223,805, 4,267,944, 4,260,075 and 4,627,823 disclose automatic inflators which automatically inflate the inflatable article upon being immersed in water, such as sea water. Automatic inflators are particularly desirable when the inflatable article is intended to be utilized during an emergency situation to inflate the inflatable article without a person's assistance or intervention. Illustrative examples of emergency signalling and rescue articles of this nature are disclosed in U.S. Pat. Nos. 2,264,321, 3,754,291, 4,498,879, 4,560,356 and 4,627,823.
Inflatable articles often include a relief valve connected through the wall of the inflatable bladder of the article The relief valve of this type typically comprises a spring-loaded valve seat which opens when the pressure inside the inflatable bladder exceeds a preset limit, thereby venting the inflatable bladder. Relief valves are most common for inflatable articles employing inflators, both automatic and manual, to prevent rupturing of the inflatable bladder upon inflation. Indeed, the volume of air contained within the gas cartridge may exceed the maximum volume of the inflatable bladder. In such instances, relief valves are essential.
Unfortunately, most relief valves include a specially-configured design which allows them to be molded through the wall of the inflation bladder. These specially-configured relief valves are more costly to manufacture than other types of available relief valves
Even when inflators are employed, most inflation articles include an inflation valve to permit oral inflation of the article in the event of inflator malfunction. Oral inflation valves are also needed to permit oral inflation and deflation of the inflatable article when the article needs to be slightly inflated or deflated, such as when the day cools off in the evening or warms up in the morning causing a decrease or increase, respectively, of the volume of air in the bladder.
Oral inflation tubes are commonly used in connection with inflatable articles. Conventional oral inflation tubes typically comprise a tubular configuration having one end integrally formed in a flange to be sealingly connected through the wall of the inflation bladder. An inflation valve is positioned in the other end of the tube. The inflation tube is designed to make it easier for the inflatable article to be inflated by a person. For example, a life vest typically includes an inflation tube which extends from a middle or lower portion of the life vest upwardly toward the face of the person wearing the life vest. In this arrangement, upon the simple bending of the person's neck, the end of the tube may be easily mouthed to inflate the bladder. The person therefore need not remove the life vest simply to inflate the same.
In addition to facilitating easy inflation, oral inflation tubes allow conventional inflation valves to be utilized. Specifically, because the inflation tube comprises a circular cylindrical configuration, many of the large variety of cylindrically-shaped inflator valves may be utilized by simply pressing the inflator valve into the end of the tube. The use of such conventional inflation valves results in a substantial cost savings over other types of valves, such as relief valves, that are specially designed to be sealed through the wall of the inflation bladder.
As should be appreciated, a relief valve and an oral inflation tube with its inflation valve, are two separate components, both of which must be sealingly installed through the wall of the bladder. As separate components, the cost of assembly is double and the risk of a leak during assembly or later during use, is doubled Hence, there presently exists a need for a way to combine the functions of both the relief valve and the inflation tube with its inflation valve so as to minimize the cost of assembly and to minimize the chance of a leak, thereby maximizing reliability and safety.
It is an object of this invention to provide an improvement which overcomes the aforementioned inadequacies of the prior art devices and provides an improvement which is a significant contribution to the advancement of the oral inflation tube art.